While NHLBI guidelines recommend daily preventive medications for all children with persistent asthma, poor adherence to these recommendations is common, particularly among poor urban children. The goal of the proposed project is to reduce morbidity for impoverished children with asthma by improving adherence to guidelines for care. This study builds on our experience with a pilot sample of 180 urban children that suggested that school-based administration of preventive asthma medications reduces asthma symptoms. However, the beneficial effects of the program were seen only among children not exposed to environmental tobacco smoke (ETS). We propose a full-scale randomized trial with a comprehensive intervention that consists of both administration of preventive asthma medications in the school (with dose adjustments according to NHLBI guidelines), and, for smoke-exposedchildren, an ETS reduction program in the home. We hypothesize that children receiving the comprehensive school-based intervention will experience less asthma-related morbidity compared to children receiving usual care. The secondary hypothesis is that, among the subgroup of smoke-exposed children, those receiving the comprehensive intervention will experience less asthma morbidity than those receiving usual care. Five hundred and thirty children ages 3- 10 years will be identified from 50 schools in the Rochester City School District, and will be assigned randomly to the school-based care group or a usual care group. Data will be analyzed to assess the overall effectiveness of the school-based intervention in reducing asthma morbidity (including symptom-free days as the primary outcome, as well as additional secondary outcome measures), evaluate whether smoke-exposed children who receive the intervention have lower asthma morbidity than smoke-exposed children who receive usual care, and establish the program's cost-effectiveness. This project may have a profound impact on public health because it presents a practical system change to assure adherence to therapy and decrease ETS exposure among impoverished children with asthma. Should it prove successful in reducing symptoms and improving the health of young urban children with asthma, it has the potential to serve as a model for improved asthma care in urban communities.